Christian rudolph



' 55 acid in aqueous emulsion.

UNITED STATES PATENT OFFICE.

CHRISTIAN RUDOLPH, OF OFFENBAOH-ON-THE-MAIN, GERMANY, ASSIGNOR TO THE FIRM OF K. OEI-ILER, OF SAME PLACE.

TRISAZO DYE.

SPECIFICATION forming part of Letters Patent No. 572,723, dated December 8, 1896.

Application filed April 10, 1896. Serial No. 586,931. (Specimens) Patented in England July 10, 1893, No. 13,402, and in Germany October 23, 1894,1I0. 86,009.

N Hg

Amidophenolsulfo-acid III.

Now if the intermediate products thus resulting from the action of one molecule of a para- 2 diamin upon one molecule of a metaamidooxysulfo-acid of the benzene series are combined with resorcin or metaphenylendiamin tetrazo dyestuffs result which are susceptible of acting upon one molecule diazonaphthionic 3o acid, thus yielding new trisazo dyestuffs.

The above-mentioned acids, amidophenolsulfo-acid III and amidocresolsulfo-acid III,

Benzidin My invention consists in the discovery that the so-called paradiamins as,for instance, benzidin, toluidin, dianisidin, &c. under suitable circumstances yield intermediate compounds with those metaamidooxysulfoacids of the benzene series which contain the OH group and NH group in the so-called meta position. Such are, for instance, the amidophenolsulfo acid III and the amido- 2o cresolsulfo-acid III, as will be seen by comparing the formulae of these acids.

SO H NH Amidocresolsulfo-acid III.

are obtained by melting anilindisulfo-acid or toluidindisulfo-acid, respectively, with alkalies. 3 5 The new trisazo dyestuffs dye unmordanted cotton from an alkaline bath brown-red t0 corinth.

As an example in which manner my invention may be carried out I shall hereinafter 40 describe the production of the dyestuff:

Azoamidophenolsulfo-acid III Azometaphenylendiamin diazonaphthionic-acid.

of ten and three-fifths (10.6) parts of the sodium salt of amidophenolsulfo-acid and the equal quantity of soda. After the formation of the intermediate product add to the mass five and two fifths (5.4) parts of phenylendiamin, and, finally, after the intermediate dyestuff has been formed, add eleven and seven-tenths (11.7) parts of diazonaphthionic Allow to stand for twenty-four (24) hours. Then heat the 'mass, add common salt in order to precipitate. the dyestuff, filter, press, and dry. The

coloring-matter thus obtained forms a black powder, which dissolves in water to a brown and in concentrated sulfuric acid to a violet to a blue solution.

lVhat I claim as my invention is- 1. The within-described process of making new trisazo dyestuffs consisting in first 'forming intermediate products by combining the paradiamins, as for instance benzidin, with a metaamidooXysulfo-acid of the benzene Series which contains the OH group and the NH group in the so-called meta position,then 7o combining these intermediate products with metaphenylendiamin or resorcin and finally causing diazonaphthionic acid to act upon the thus resulting intermediate dyestuffs.

2. As a new article of manufacture, the new IO blue solutions, and dyeing unmordanted cotton from an alkaline bath brown-red to corinth, substantially as herein described.

In testimony whereof I have signed my name to this specification in the presence of tWo subscribing Witnesses.

CHRISTIAN RUDOLPH. lVitnesses:

DEAN MASON, JEAN GRUND. 

